Summer is just around the corner.  It’s a time of year when people, and pets, spend more time outside. There is nothing like relaxing on the back porch listening to the hum of the cicadas, but if you have certain types of trees on your property, you should be aware of the dangers they can present to some pets.  Below is a list of trees found in Tulsa that can be dangerous to pets, but it is not all inclusive.


The seedpods from mimosas can present a danger to pets.

While gorgeous to look at, the beauty of the mimosa tree is only skin deep.  The blossoms, feathery and fluffy, look like cotton candy and have an intoxicating scent.  However, its seedpods are poisonous to pets as they interfere with the neurotransmitters which send signals between nerve cells.  Consuming mimosa seeds can result in muscle tremors, spasms, and convulsions.


Everyone loves a good fruit tree.  However, some species of fruit trees, particularly apple/crabapple, apricot, cherry, peach, and plum can be toxic to dogs, cats, and horses.  The stems, leaves, and seeds all contain a chemical that once ingested, is metabolized into cyanide.  Ingestion of the stems, leaves, and seeds can result in dilated pupils, difficulty breathing, panting, darkened gum and urine, seizures, and shock.  It is important to note that the chemical concentration is highest in the fall making fallen leaves more dangerous than living ones.

The stems, leaves, and seeds on fruit trees, including cherry, all contain a chemical that once ingested, is metabolized into cyanide.


The entire boxwood tree is poisonous to dogs, both orally and topically.

The boxwood is a flowering evergreen tree and is often used in gardens or yards as shrubs or dividers.  The entire tree is poisonous to dogs, both orally and topically, so it is best not to have them anywhere near where a dog will have access.  A very small amount can be toxic and eating just one leaf can cause significant symptoms.  The tree contains alkaloid that if ingested, can cause congestion of the heart, lungs, liver, kidneys, and spleen which can lead to organ shutdown and death. Topical poisoning can result in excessive skin irritation, itching, and redness.


Surprisingly, the ubiquitous oak tree can present a danger to pets if they ingest the acorns from the tree.  Acorns contain a toxic element called tannic acid and when ingested, can cause vomiting, diarrhea, and abdominal comfort.  There is also the potential for obstruction due to the size and shape of the acorns.


It is important to make sure that dogs do not ingest acorns from oak trees. They have a toxic element and the acorns themselves can cause obstruction.

The red maple is especially deadly for horses.

While the toxic element of a red maple is unknown, if a dog, cat, or horse ingests the leaves, it can lead to impaired red blood cell function and may cause abdominal pain, change in urine color, darkened eye and mouth membranes, lack of appetite, and lethargy.  This tree is especially deadly for horses and if you have them on your property, they should be removed to ensure that livestock are unable to reach them.


The danger with black walnut trees is the potential for mold that grows on the nuts.  The nuts are toxic for horses and dogs, but not cats.  If ingested, the mold can lead to fluid buildup in the legs, increased heart and respiratory rate, and increased body temperature, among other things.

The mold on the nuts from black walnuts can be toxic to dogs.

While nice weather is certainly something both you and your pets should enjoy, you should be aware of the names of all the trees on your property that a pet may have access to.  If the tree is dangerous to pets, you should ensure that your pet is unable to access the tree or anything that may fall from the tree.  If restricting access is not an option, you should consider removal to protect your pets.  If you suspect that your pet has had access to or ingested something poisonous from a tree and is exhibiting symptoms, you should contact a vet immediately.